Hydraulic governor



Nov. 1, 1955 7 A. e. LAUTZENHISER 2,722,205

HYDRAULIC GOVERNOR Filed April 13, 1955 2 Sheets-Sheet 1 INVENTOR ATTORNEY Nov. 1, 1955 A. G. LAUTZENHISER 2,722,205

HYDRAULIC GOVERNOR Filed April 13, 1953 2 Sheets-Sheet 2 70 SERVO OM PIPE 551/195 007257 llVENTOR ZWJM ATTORNEY United States Patent HYDRAULIC GOVERNOR Argyle G. Lautzenhiser, Anderson, Ind., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application April 13, 1953, Serial No. 348,319

14 Claims. (Cl. 123-103) This invention relates to engine governors and, more particularly, to engine governors of the hydraulically actuated variety for limiting the maximum speed of an internal combustion engine.

The invention aims generally toward providing an improved hydraulic over-speed governor which is of simple and inexpensive construction, which is positive and reliable in operation, which employs a minimum number of parts and is possessed of a high degree of sensitivity and stability over a wide range of operating conditions.

In distinction to prior art engine governors such as may be combined with the engine distributor and utilize the engine manifold vacuum pressure as a source of operating power, the governor of the present invention is combined with the engine lubricating oil pump and utilizes the engine pressure oil that provides a positive unfailing source of engine developed fluid pressure over a wide range of operating conditions. By reason of its compact and novel design the invention is adapted to be readily installed on the engine oil pump with little or no modification thereof and to be driven by the pump shaft so as not to require a separate drive or power take-off shaft therefor. The governor control unit contains a plurality of uniquely associated and interconnecting fluid passages which are so formed therein as to require a minimum number of simple machining operations and to eliminate the use of core plugs therefor. By reason of the location and arrangement of parts, the invention dispenses with the need for excessive lengths of connecting tubing extending about the exterior of the engine between the components of the governor system and employs but a single short length of hydraulic tubing, which, like all the other fluid carrying members of the invention, is confined within the interior of the engine above the oil sump thereof, whereby loss of engine oil is prevented should a leak or rupture develop therein. Also the interior location of the governor within the engine tends to discourage unauthorized personnel from tampering with the governor speed setting.

The above and other objects, features and advantages of the present invention will appear more fully from the following detailed description and drawings wherein:

Fig. 1 is a front elevation view with parts broken away and in section illustrating an overspeed control system which includes a governor installation in accordance with a preferred embodiment of the present invention;

Fig. 2 is an enlarged fragmentary view of a part of the apparatus of Fig. 1;

Fig. 3 is an elevation view taken on the line 33 of Fig. 4 with parts broken away and sectioned to illustrate a related form of hydraulic governor in accordance with another embodiment of the invention; and

Fig. 4 is an end view with parts broken away and sectioned of the structure of Fig. 3.

Referring to Fig. 1 of the drawings, the hydraulic speed control system of the present invention comprises, in

general, an engine lubricating oil pump 10, a governor control unit 12 and a pressure responsive servo device 14 is interiorly mounted from a Wall 16 of the engine crank case 17 and is connected to the throttle valve 18 (Fig. 1) associated with the carburetor of the engine. The throttle valve may be spring biased towards closed position in the usual manner as is shown in my Patent 2,664,868. An oil pan 20 detachably connected to the engine crank case forms an oil sump containing a quantity of lubricating oil, which is supplied to the pump inlet through a float type oil strainer 22 of conventional design.

The oil pump 10, which is mounted in an opening in the engine crank case communicating with the oil sump, may be of the commonly employed high capacity gear type developing substantially full engine pressure at about one-third engine speed and comprises a generally one-piece housing 24, which is formed with an enlarged open-ended lower portion 24a having a pump chamber therein, and a pair of axially extending spaced shafts 26 and 28 respectively mounting in the pump chamber of the pump housing a driver gear 30 and an idler gear 32 meshing with and driven by the driver gear. The driver shaft 26 extends axially through the pump housing and is adapted to be driven at its upper end from a gear on the engine driven cam shaft, which is mounted for rotation in the crank case of the engine. The end cover normally provided with the pump housing is replaced by a governor adaptor structure 36 which forms a detachable end wall for the pump chamber and provides a mounting for the rotating portion of the governor control unit.

The governor adaptor 36 may be a cast one-piece structure having a plate or cover portion 38, an axial downwardly extending arcuate wall portion 40, an end portion 42 spaced from and parallel to the said cover portion 38 and an integrally formed generally L-shaped conduit 44 having an arm 45 that communicates with the inlet or low pressure side of the pump through the cover plate portion 38 and another arm 46 suitably connected to the outlet 48 of the strainer 22 in the oil pan 20. The cover plate portion 38 has a boss 50, which is formed on the outer face thereof opposite the pump chamber, with a shaft bore 51 coaxial with the pump shaft 26 and extending therethrough. The inner face of the plate portion 38 has a pressure pocket 52 formed therein on the high pressure side of the pump chamber, and a diagonal pressure supply passage 54 is provided between the pocket 52 and the shaft bore 51 for supplying a small quantity of pressure oil to the governor control unit, as will appear more fully below. The spaced end portion 42 of the governor adaptor has a boss 56 formed on the underside thereof and has a shaft bore 57 extend ing partway therein and coaxial with the bore 51 in boss 50. Communicating with the bore 57 is a transverse pressure discharge passage 58in the boss 56.

The movable elements of the governor control unit 12 include a governor shaft portion 66, which is supported for rotation in the journals provided by the bosses 50 and 56 of the governor mounting structure, and a centrifugally unbalanced slide valve assembly 62, which is carried by the governor shaft portion and is contained in a partially defined open chamber formed by the plate portion 38, the arcuate wall portion 40 and the end portion 42, all of the governor adaptor structure 36. The governor shaft 60, which is inserted from the upper face of the adaptor plate portion 38 is supported principally at its lower end in the bottom wall of the bored boss 56 and has a nib or drive tang 64, which is formed at the upper end thereof extending through the adaptor plate portion 38 into the pump chamber and is received in a slot 65 formed in the adjacent end of the drive shaft 26 of .the pump, thereby to provide positive drive for the governor control unit. The governor shaft is annularly grooved as at 68, near its upper end portion in the shaft bore 51 and is provided with a plurality of fluid passages therein including a fluid pressure inlet passage 70, a transverse passage or crossbore 72 spaced from the shaft groove 68, a fluid pressure application or outlet passage 74 and a notch or slot 76 forming a pressure relief passage at the end of the cross-bore 72, through which the pressure inlet and outlet passages 70 and 74 may communicate with atmosphere, as will appear below. The pressure inlet passage 70 and the pressure outlet passage 74 are oppositely diagonally inclined and have their adjacent ends in spaced or staggered relation branching from the cross-bore 72, substantially as shown. The opposite ends of the diagonal branch passages 70 and 74 respectively communicate with the annular groove 68 and with the bore 57 and discharge passage 58 in the lower boss 56 of the adaptor stucture.

As best shown in Fig. 2, the control valve assembly 62 comprises a valve spool or stem 80, a centrifugal flyweight 82, a balance spring 84 and a spring tensioning nut 86. The valve spool 80 is slidably fitted in the cross-bore 72 in the governor shaft 60 and has an annular groove 88 between the ends thereof, which serves to establish fluid communication between the pressure outlet passage 74 and pressure relief passage 76 or the pressure inlet passage 70 and pressure outlet passage 74 or all three of said passages depending upon the speed of the engine. The valve spool 80 has a portion normally closing the inlet branch passage 70 which portion may be provided with a plurality of spaced circumferential grooves 89 that serve to reduce the friction of the valve spool and cause a relatively free and positive valve action by providing somewhat of a floating action to the spool within the cross-bore 72.

The centrifugal fly-weight 82 is bored and counterbored, as shown in Fig. 2, to accommodate a bushing 90 of synthetic rubber or the like, which serves as a torsional vibration damper, and is retained on the valve spool by a spring clip 92 and an enlarged integrally formed head 80a on one end of the spool. The tensioning spring 84, which is located at the end of the valve spool opposite the fly-weight 82, is seated at one of its ends in a spot-faced groove or slot 94, which is formed in the surface of the governor shaft and coaxial with the cross-bore 72 therein, and is seated at its other end against the spring tensioning nut 86, which is threaded on a reduced end portion of the valve spool.

If desired the oil pan 20 may be provided with a detachable plate 98 covering an opening 100 in a sidewall thereof through which a suitable tool such as a socket wrench or the like may be inserted to engage the spring tensioning nut 86, thereby to adjust the initial governor speed setting.

The pressure discharge passage 58 in the lower end of the governor adaptor structure has a threaded opening therein which forms a discharge port from the governor control unit and threadably receives one end of a short length of connecting tubing 102 the other end of which is connected to the pressure responsive servo device 14. The device 14 may be a conventional pressure diaphragm structure, one side of the diaphragm 104 of which is adapted to be exposed to the fluid pressure regulatively applied thereto from the governor control unit and the other side of which may be exposed to atmosphere and is connected with a push rod 106 shown extending through the engine wall 16 and operatively connected to the engine throttle valve 18 (Fig. 1) below the carburetor in the intake manifold of the engine.

The Weight of the governor fly-weight 82, the adjusted compressive strength of the balance or tensioning spring 84 and the speed of revolution of the governor shaft 60 determines the extent that the valve spool 80 moves to govern the flow of fluid under pressure from the oil pump to the pressure responsive device 14.

With the parts of the control system in the normal position shown, starting of the engine causes rotation of the pump shaft 26 and causes engine lubricating oil pressure to be supplied from the pressure side of the pump chamber to the pressure pocket 52 and the pressure supply passage 54 in the adaptor plate portion 38, the annular groove 68 in the governor shaft and the pressure inlet branch passage 70 extending from the annular shaft groove 68 to the crossbore 72 in which the valve stem is normally positioned to block the inner end of this branch passage. With the valve stem in the normal position shown, the annular groove 88 therein registers with the pressure relief slot or passage 76 and the pressure outlet branch passage 74 so as to relieve fluid pressure on the pressure diaphragm 14 and thus to reference the system to atmosphere.

Upon an increase in the speed of the pump shaft 26 driven by the engine to a value sufficient to cause the centrifugal flyweight 82 and valve stem 80 to move radially outwardly of the governor shaft against the force of the balance spring 84 on the valve stem, the valve stem groove 88 will be moved initially into momentary registry with the inner end of all three passages 70, 74 and 76 in the governor shaft, and then will be finally moved into registry with the diagonal branch passages 70 and 74 when substantially full lubricating oil pressure will be applied to the pressure outlet or application passage 74 and to the diaphragm pressure chamber in the pressure operated throttle actuating device. The momentary application of pressure from the pressure inlet passage 70 to both the pressure relief slot or passage 76 and the pressure outlet passage 74 limits the sudden increase of pressure in the diaphragm chamber so as to prevent over-shooting and consequent hunting that otherwise would obtain.

The governor structure illustrated in Figs. 3 and 4 is generally similar to that of Figs. 1 and 2 and differs principally therefrom in that the governor control unit 12 is carried in an integrally formed extension of the idler gear pump shaft 28 and is enclosed in a pressure relief chamber defined by a two-piece adaptor structure comprising a separator plate 112 and cup-like cover member 114, substantially as shown. The separator plate 112, which forms a detachable end wall for the pump chamber, is generally similar to the adaptor plate portion 38 of Fig. l and includes a pressure pocket 52' and pressure supply passage 54 therein through which pressure oil is supplied to an annular groove 68' in the idler gear shaft. The idler gear shaft contains a pressure inlet passage 70' and pressure outlet passage 74 both branching from a crossbore 72' therein which carries a centrifugally unbalanced spinner control or slide valve unit 62 similar to that shown in Fig. 2. The pressure relief passage 76 formed in the side of the idler gear shaft extension and at one end of the cross-bore 72 therein establishes communication with the enclosed governor or pressure relief chamber 110 which communicates with the engine oil sump and atmosphere through an opening 116 provided in the detachable end cover 114 thereof.

What is claimed is:

1. In combination, an engine having a throttle, a walled engine housing and a fluid pressure hydraulic system including a fluid sump and an engine driven pump within the interior of the engine housing, fluid pressure responsive means having a part extending outside of said engine housing and connected to said engine throttle and a fiuid carrying part within said housing, fluid conduit means Within the interior of said engine extending between said pump and said -fluid carrying part of said fluid pressure responsive means, and a centrifugal governor including a centrifugally unbalanced governor valve within the interior of said housing and driven by said engine, said governor valve being connected in said fluid conduit means between said pump and said fluid pressure responsive means for controlling fluid communication therethrough in accordance with the speed of said engine.

2. In a speed controlling mechanism for an engine having a throttle, a crank case and a fluid pressure hydraulic system including a fluid sump and an engine driven pump within the interior of the engine crank case, the combination of fluid pressure responsive means having a fluid carrying part within the interior of said engine and an actuator element connected to said throttle outside of said crank case, fluid conduit means within the interior of said engine extending between said pump and said fluid carrying part of said fluid pressure responsive means, and a centrifugal governor including a centrifugally unbalanced governor valve driven by said pump within the interior of said engine and connected in said fluid conduit means between said pump and said fluid pressure responsive means for controlling fluid communication therethrough in accordance with speed of said engine.

3. In combination, an engine having a throttle and a source of engine developed fluid pressure including an oil sump and an oil pump, said oil pump having a pump chamber therein, separate inlet and outlet passages communicating with the pump chamber and connected to different parts of the engine, and a pump shaft driven by the engine, a centrifugal governor driven by said pump shaft, said governor having a pressure inlet passage communicating with said pump chamber and a pressure outlet passage and a centrifugally unbalanced control valve between said passages for controlling fluid communication therethrough, fluid pressure responsive means having a part connected to said engine throttle and a fluid carrying part within the interior of said engine and a fluid conduit within the interior of the engine connected to the said pressure outlet passage of said governor and the said fluid carrying part of said fluid pressure responsive means.

4. In combination with an engine having a throttle and a source of engine developed fluid pressure including an oil sump and an engine driven oil sump above said oil sump within the interior of the engine, said oil pump having a housing, a pump chamber in said housing, said housing having a separate inlet passage and outlet passage communicating with said chamber and a shaft rotatable in said housing, a centrifugal governor adjacent said pump chamber and having a shaft driven by said pump shaft, said governor shaft having a plurality of fluid passages therein including a generally transverse passage, a pressure inlet passage communicating with said pump chamher and said transverse passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage, a centrifugally unbalanced valve element in said transverse passage for controlling fluid communication between said pressure inlet passage and said pressure outlet passage, fluid pressure responsive means within the interior of said engine and having a part operatively connected to said throttle outside of said engine and a fluid conduit connected to the said fluid pressure responsive means and the said fluid outlet passage of said governor.

5. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber therein, a separate inlet passage and outlet passage in said housing communicating with said pump chamber, and a pump shaft rotatably mounted in said housing, a governor without said pump chamber and driven by said pump shaft, said governor including a rotatable shaft portion having a plurality of passages therein including a generally transverse passage, a pressure inlet passage communicating with said pump chamber and said transverse passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage, and a centrifugally unbalanced control valve slidable in said transverse passage for regulating fluid communication through said pressure inlet passage and said pressure outlet passage, the said outlet passage of said governor shaft portion being independent of said inlet passage and said outlet passage of said pump housing,

6. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber therein, a separate inlet passage and outlet passage in said housing communicating with said pump chamber and a pump shaft rotatably mounted in said housing, a governor without said pump chamber and driven by said pump shaft, said governor including a rotatable shaft portion having a plurality of passages therein including a transverse passage, a pressure inlet passage communicating with said pump chamber and said transverse passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage, a centrifugally unbalanced control valve element slidable in said transverse passage for regulating fluid communication through said pressure inlet passage and said pressure outlet passage, and a cover detachably mounted to said pump housing and enclosing said governor therein, the said outlet passage of said governor shaft portion being independent of said inlet passage and said outlet passage of said pump housing.

7. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber therein and a separate inlet passage and outlet passage in said housing communicating with said pump chamber, an end wall for said chamber having a shaft bore therein and a pressure supply passage extending between said pump chamber and said shaft bore, a first shaft rotatable in said housing, a second shaft driven by said first shaft and extending without said pump chamber through said shaft bore, said second shaft having atplurality of. passages therein including a transverse passage, a pressure inlet passage communicating'with said supply passage in said shaft bore and said transverse'passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage and a centrifugally unbalanced control valve slidable in said transverse passage and cooperating with said pressure inlet passage and said pressure outlet passage for regulating fluid communication therethrough, said pressure outlet passage of said second shaft being independent of said inlet passage and said outlet passage of said pump housing.

8. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber therein and a separate inlet passage and outlet passage communicating with said pump chamber, an end Wall for said chamber having a shaft bore therein and a pressure supply passage extending between said pump chamber and said shaft bore, a first shaft rotatable in said housing, a second shaft coaxial with and driven by said first shaft, said second shaft extending through said shaft bore in said end Wall and having a plurality of passages therein including a transverse passage, a pressure inlet passage communicating with said pressure supply passage and said transverse passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage and a centrifugally unbalanced control valve slidable in said transverse passage and cooperating with said pressure inlet passage and said pressure outlet passage for establishing fluid communication therethrough, the said pressure outlet passage of said second shaft being independent of said inlet passage and outlet passage of said pump housing.

9. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber therein and a separate inlet passage and outlet passage communicating with said pump chamber, an end wall for said chamber having a shaft bore therein and a pressure supply passage extending between said pump chamber and said shaft bore, a first shaft rotatable in said housing, a second shaft spaced from and driven by said first shaft, said second shaft extending through said shaft bore in said end wall and having a plurality of passages therein including a transverse passage, a pressure inlet passage communicating with said pressure supply passage and said transverse passage and a pressure outlet passage communicating with pressure inlet passage through said transverse passage and a centrifugally unbalanced control valve slidable in said transverse passage and cooperating with said pressure inlet passage and said pressure outlet passage in said second shaft for establishing fluid communication therethrough, the said pressure outlet passage of said second shaft being independent of said inlet passage and said outlet passage of said pump housing.

10. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber therein and a separate inlet passage and outlet passage communicating with said-pump chamber, a detachable plate forming an end wall for said chamber, said plate having a shaft bore therein and a pressure supply passage extending between said pump chamber and said bore, a pump shaft rotatably mounted in said housing and extending without said pump chamber through said shaft bore, the extension of said shaft without said pump chamber being annularly grooved in said shaft bore to communicate with said plate passage and having a plurality of fluid passages therein including a transverse passage spaced from the shaft groove, a pressure inlet passage extending between the said shaft groove and said transverse passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage, and a centrifugally unbalanced control valve slidable in said transverse passage and cooperating with said pressure inlet passage and pressure outlet passage in said shaft extension for establishing fluid communication therethrough, the said pressure outlet passage in said shaft extension being independent of said inlet passage and said outlet passage of said pump housing.

11. A pump driven hydraulic speed governor comprising, in combination, a Walled housing having a pump chamber therein and a separate inlet passage and outlet passage communicating with said pump chamber, a detachable plate forming an end wall for said chamber, said plate having a shaft bore therein and a pressure supply extending between said pump chamber and said bore, a pump shaft rotatably mounted in said housing and extending without said pump chamber through said shaft bore, the extension of said shaft without said pump chamber being annularly grooved in said shaft bore to communicate with said plate passage and having a plurality of fluid passages therein including a transverse passage spaced from the shaft groove, a pressure inlet passage exr tending between the said shaft groove and said transverse passage and a pressure outlet passage communicating with said pressure inlet passage through said transverse passage, a centrifugally unbalanced control valve slidable in said transverse passage and cooperating with said pressure inlet passage and pressure outlet passage in said shaft extension for establishing fluid communication therethrough, and a detachable cover connected to said plate and enclosing said shaft extension, said pressure outlet passage of said shaft extension being independent of said inlet passage and said outlet passage of said pump housing.

12. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber and a governor chamber therein separated by a v detachable wall of said housing, said housing having a separate inlet passage and outlet passage communicating with said pump chamber therein, a pair of spaced shafts rotatable in said housing and respectively mounting in the said pump chamber thereof a driver gear and an idler gear intermeshing with said driver gear, said separating wall having a shaft bore therein to receive said idler gear shaft, said idler gear shaft extending through said separating wall into said governor chamber and having a plurality of fluid passages therein including a transverse passage, a pressure inlet passage and a pressure outlet passage both communicating with said transverse passage, said separating wall having a pressure supply passage extending between said pump chamber and said shaft bore to supply fluid under pressure to said pressure inlet passage and a centrifugally unbalanced control valve slidable in said transverse shaft passage and cooperating with said pressure inlet passage and pressure outlet passage therein for establishing fluid communication therethrough, the said pressure outlet passage in said idler gear shaft being independent of said inlet passage and said outlet passage of said pump housing.

13. A pump driven hydraulic speed governor comprising, in combination, a walled housing having a pump chamber and a governor chamber therein, said housing having a separate inlet passage and outlet passage communicating with said pump chamber, a detachable wall separating said chambers, said wall having a shaft bore therein and a pressure supply passage extending between said pump chamber and said shaft bores, first shaft rotatable in said housing, a second shaft driven by said first shaft and extending through said shaft bore in said separating wall into governor chamber, said second shaft being annularly grooved in said shaft bore to communicate with said pressure supply passage and having a plurality of fluid passages therein including a transverse passage spaced from the annular groove thereon, a pressure inlet passage extending between said annular groove and said transverse passage, a pressure outlet passage communicating with said pressure inlet passage through said transverse passage and a pressure relief passage communieating with said transverse passage and said governor chamber and a centrifugally unbalanced control valve slidable in said transverse passage and cooperating with said pressure inlet passage and pressure outlet passage for establishing fluid communication therethrough, said control valve having a grooved stern normally closing communication between said pressure inlet passage and said pressure relief passage and registering with said transverse passage and said pressure outlet passage, the said pressure outlet passage of said second shaft being independent of said inlet passage and said outlet passage of said pump housing.

14. In combination with a lubricating oil pump having a housing, a pump chamber in said housing, a separate inlet passage and outlet passage communicating with said pump chamber and a pump shaft rotatable in said housing, a speed governor comprising an adaptor plate forming an end cover for said pump housing and an open mounting for the governor without said pump chamber, said cover having a shaft bore therein and a pressure supply passage extending between said pump chamber and said bore, a governor shaft journaled in said cover mounting and extending into said housing through said bore for rotation by said pump shaft, said governor shaft having an annular groove thereon communicating with said pressure supply passage in said cover mounting, a valve bore spaced from said annular groove and extending transversely therethrough, a fluid pressure inlet passage extending between said annular groove and said valve bore, a fluid pressure outlet passage communicating with said fluid inlet passage through said valve bore and an atmospheric pressure relief passage communicating with said valve bore, and a centrifugally unbalanced control valve including an annularly grooved valve spool slidably mounted in and extending through said valve bore, said spool having spring means thereon urging the spool to a position closing communication between said pressure inlet passage and said pressure relief passage, said valve spool being movable against the spring loading thereof responsive to the rotation of said governor shaft whereby to close communication gradually between said pressure outlet passage and said pressure relief passage and to establish communication gradually between said pressure inlet passage and said pressure outlet passage as the speed of ro- 9 10 tation of said governor shaft increases, the said pressure 1,811,850 Hutf June 30, 1931 outlet passage of said governor shaft being independent 2,260,576 Maybach Oct. 28, 1941 of said inlet passage and said outlet passage of said pump 2,356,679 Mallory Aug. 22, 1944 housing. 2,412,289 Pugh et a1 Dec. 10, 1946 5 2,433,954 Lapsley Jan. 6, 1948 References Cited in the file of this patent UNITED STATES PATENTS 1,329,385 Egger Feb. 3, 1920 

